diff --git a/lib/binary_to_decimal.rb b/lib/binary_to_decimal.rb
index 439e8c6..9cdfee9 100644
--- a/lib/binary_to_decimal.rb
+++ b/lib/binary_to_decimal.rb
@@ -4,6 +4,16 @@
 # The least significant bit is at index 7.
 # Calculate  and return the decimal value for this binary number using
 # the algorithm you devised in class.
+
+
 def binary_to_decimal(binary_array)
-  raise NotImplementedError
-end
+  decimal = 0
+  i = 1
+  binary_array.each do |value|
+    power =  binary_array.length - i
+    number = value * (2 ** power)
+    decimal += number
+    i += 1
+  end
+  return decimal
+end
\ No newline at end of file
diff --git a/test/binary_to_decimal_test.rb b/test/binary_to_decimal_test.rb
index ba17713..5fb557d 100644
--- a/test/binary_to_decimal_test.rb
+++ b/test/binary_to_decimal_test.rb
@@ -6,28 +6,28 @@
   it "From 10011001 to 153" do
     binary_array = [1, 0, 0, 1, 1, 0, 0, 1]
     expected_decimal = 153
-
+    
     binary_to_decimal(binary_array).must_equal expected_decimal
   end
-
+  
   it "From 00001101 to 13" do
     binary_array = [0, 0, 0, 0, 1, 1, 0, 1]
     expected_decimal = 13
-
+    
     binary_to_decimal(binary_array).must_equal expected_decimal
   end
-
+  
   it "From 10000000 to 128" do
     binary_array = [1, 0, 0, 0, 0, 0, 0, 0]
     expected_decimal = 128
-
+    
     binary_to_decimal(binary_array).must_equal expected_decimal
   end
-
+  
   it "From random binary to decimal" do
     binary_array = Array.new(8) { rand(0..1) }
     expected_decimal = binary_array.join.to_s.to_i(2)
-
+    
     binary_to_decimal(binary_array).must_equal expected_decimal
   end
 end